¹observation

abdication, aberration, abjuration, abnegation, abrogation, acceptation, acclamation, accusation, activation, adaptation, adjuration, admiration, adoration, adulation, adumbration, affectation, affirmation, aggravation, aggregation, agitation, allegation, allocation, amputation, alteration, altercation, animation, annexation, annotation, appellation, application, approbation, arbitration, arrogation, aspiration, assignation, attestation, augmentation, automation, aviation, avocation, blaxploitation, botheration, calculation, calibration, cancellation, carbonation, castigation, celebration, cerebration, chlorination, circulation, cogitation, collocation, coloration, combination, comfort station, commendation, commutation, compensation, complication, computation, concentration, condemnation, condensation, confirmation, confiscation, conflagration, conformation, confrontation, congregation, conjugation, connotation, consecration, conservation, consolation, constellation, consternation, constipation, consultation, consummation, contemplation, conurbation, conversation, convocation, copulation, coronation, corporation, correlation, corrugation, crenellation, crop rotation, culmination, cultivation, cumulation, cybernation, decimation, declamation, declaration, declination, decoration, dedication, defamation, defecation, deformation, degradation, dehydration, delectation, delegation, demarcation, demonstration, denigration, denotation, depilation, deportation, depravation, depredation, deputation, derivation, derogation, desecration, designation, desolation, desperation, destination, detestation, detonation, devastation, deviation, dislocation, dispensation, disputation, dissertation, dissipation, distillation, divination, domination, education, elevation, elongation, emanation, embarkation, embrocation, emendation, emigration, emulation, enervation, escalation, estimation, evocation, exaltation, excavation, excitation, exclamation, exculpation, execration, exhalation, exhortation, exhumation, expectation, expiation, expiration, explanation, explication, exploitation, exploration, exportation, expurgation, extirpation, exultation, fabrication, fascination, federation, fenestration, fermentation, fibrillation, figuration, filling station, fire station, flagellation, fluoridation, fluctuation, forestation, formulation, fornication, fragmentation, fulmination, fumigation, gene mutation, generation, germination, glaciation, graduation, granulation, gravitation, habitation, hesitation, hibernation, hyphenation, ideation, imitation, immigration, immolation, implantation, implication, importation, imprecation, imputation, incantation, incarnation, inclination, incrustation, incubation, indentation, indication, indignation, infestation, infiltration, inflammation, information, inhalation, innovation, inspiration, installation, instigation, insulation, integration, intimation, intonation, inundation, invitation, invocation, irrigation, irritation, iteration, jubilation, laceration, lamentation, lamination, legislation, levitation, liberation, limitation, lineation, liquidation, litigation, lubrication, lucubration, maceration, machination, malformation, masturbation, maturation, mediation, medication, meditation, melioration, menstruation, ministration, mitigation, moderation, modulation, molestation, motivation, mutilation, navigation, nomination, obfuscation, objurgation, obligation, occupation, operation, orchestration, ordination, oscillation, osculation, ostentation, ovulation, oxidation, pagination, palpitation, penetration, percolation, perforation, permeation, permutation, perpetration, perspiration, perturbation, pigmentation, pixilation, police station, pollination, population, postulation, power station, predication, preparation, presentation, preservation, proclamation, procreation, profanation, prolongation, promulgation, propagation, prorogation, protestation, provocation, publication, punctuation, radiation, recantation, recitation, reclamation, re-creation, recreation, reformation, refutation, registration, regulation, rehydration, relaxation, relocation, renovation, reparation, replication, reprobation, reputation, reservation, resignation, respiration, restoration, retardation, revelation, revocation, ruination, rumination, rustication, salutation, sanitation, saturation, segmentation, segregation, separation, sequestration, service station, sexploitation, simulation, situation, speciation, speculation, spoliation, stimulation, stipulation, strangulation, structuration, stylization, subjugation, sublimation, suffocation, syncopation, syndication, tabulation, termination, T formation, titillation, toleration, transfer station, transformation, translocation, transmigration, transmutation, transpiration, transplantation, transportation, trepidation, tribulation, ulceration, ululation, undulation, urination, vaccination, vacillation, validation, valuation, variation, vegetation, veneration, ventilation, vindication, violation, visitation, weather station